Turbos not kicking in

[HWG09]

So I'm looking at purchasing an '86 944 Turbo and was out driving it for the second time this weekend. It drives alright but the turbos don't really kick in. You can hear them spooling and see the boost but never delivers the punch.

Any idea on the cause of that? Am I looking at a turbo rebuild or a new one? There's a bit of hesitation in 2nd gear so wondering if there are some vacuum leaks.

Haven't bought the car yet but wanted to do some research to adjust my offer accordingly.

Thanks.

[TrailRider]

Sounds like vacuum leaks. Is the boost gauge on the dash going above 1 Bar? If not than no boost is being generated.

[944 Ecology]

Of course, you realize that a 944 turbo only has one turbocharger... If you're expecting more than that, you will be disappointed...

[HWG09]

Originally Posted by TrailRider

Sounds like vacuum leaks. Is the boost gauge on the dash going above 1 Bar? If not than no boost is being generated.

Yes, it goes from about 1 to 4.

Thinking vacuum leak an issue especially with that hesitation in 2nd.

[cockerpunk]

Originally Posted by HWG09

Yes, it goes from about 1 to 4.

Thinking vacuum leak an issue especially with that hesitation in 2nd.

the stock boost gauge does not go to 4 bar, nor should a 944 turbo ever run 4 bars of boost.

[HWG09]

Originally Posted by cockerpunk

the stock boost gauge does not go to 4 bar, nor should a 944 turbo ever run 4 bars of boost.

Then I'm looking at the wrong thing.

[cockerpunk]

Originally Posted by HWG09

Then I'm looking at the wrong thing.

yeah maybe the oil gauge?

the boost gauge is under the tach. it read from .4 bar, to 2 bar. a stock 944 turbo should run a bit under 1 bar at idle, but when at WOT and above about 3500 rpm, be at 1.8 bar. most aftermarked 944 turbos will peg the stock gauge at 2 bar.

[HWG09]

Originally Posted by cockerpunk

yeah maybe the oil gauge?

the boost gauge is under the tach. it read from .4 bar, to 2 bar. a stock 944 turbo should run a bit under 1 bar at idle, but when at WOT and above about 3500 rpm, be at 1.8 bar. most aftermarked 944 turbos will peg the stock gauge at 2 bar.

Gotcha, thanks.

[Pete R]

Are you sure it's a turbo car?

[nize]

can you post up a photo of the engine bay?

[AaronM]

Originally Posted by cockerpunk

a stock 944 turbo should run a bit under 1 bar at idle

Only if it has a MASSIVE vacuum leak...

A stock 944 turbo should run between about 0.33 and 0.4 bar at warm idle.

The gauge should read roughly 1 bar when the engine is off and the key is in the "run" position because in that case it's reading atmospheric pressure.

Originally Posted by HWG09

Yes, it goes from about 1 to 4.

Sounds like you're looking at the oil pressure gauge. In which case the car has problems. At hot idle there should be at least 2 bar of oil pressure. With only 1 bar of hot oil pressure you're looking at rod bearing problems in the car's future. Or the oil pressure sender / gauge is dying. These cars should normally see between 2.0 and 4.5 bar of oil pressure, with 2 bar being at idle and 4.5 bar being at redline.

[HWG09]

Thanks for the additional posts. The seller took the car in and they said it's either a clogged fuel filter or vacuum leak which isn't too scary.

Good news is the guy is going overseas with the Air Force this week so he is selling me the car for a song!

Don't want to jinx anything yet b/c I don't pick it up till tomorrow but I will post pics and updates on all this once the transaction is complete.

[944 Ecology]

[HWG09]

Originally Posted by 944 Ecology

Ha, not sure what this is referencing but guessing it can't be good.

[AaronM]

Originally Posted by HWG09

Ha, not sure what this is referencing but guessing it can't be good.

It probably has to do with:

Originally Posted by HWG09

The seller took the car in and they said it's either a clogged fuel filter or vacuum leak which isn't too scary.

This is something your mechanic should look at. You shouldn't be trusting the seller to find out what's wrong with the car.

Also, if a mechanic cannot diagnose the difference between a clogged fuel filter and a vacuum leak, that mechanic isn't someone you should allow to work on your car.

Originally Posted by HWG09

Good news is the guy is going overseas with the Air Force this week so he is selling me the car for a song!

This is a common scam used to stop people from worrying about why a car has a suspiciously low price.

[DannoXYZ]

Remember, these are old cars with lots of wear and tear. The Turbo models can be driven much faster and harder than the non-turbo versions, so you can be looking at more worn-out brakes and suspension. The engine itself is typically always more worn out than a 944 with similar mileage.

Get it inspected by your own mechanic who's familiar with 944 Turbos!!! It's definitely worth the cost as there is no such thing as an inexpensive 944 Turbo. In fact, the cheaper the price, most likely you'll have to spend way more on repairs to get it back to decent running shape. Most of the time, it'll cost you less in money and headaches to get one that costs more and requires no major surgeries.

There's an endless list of people who've bought a "cheap" $5000 944 Turbo that had to spend an additional $5000-10000 to get it running.

[guru944]

Check for exhaust leak.
Check when car starts up cold. Use the tissue paper test. if you can"t feel heat or hear it.
Check exhaust o-rings between Header and cross over pipe and at wastegate "Y" below.

Later....

[HWG09]

Originally Posted by AaronM

It probably has to do with:



This is something your mechanic should look at. You shouldn't be trusting the seller to find out what's wrong with the car.

Also, if a mechanic cannot diagnose the difference between a clogged fuel filter and a vacuum leak, that mechanic isn't someone you should allow to work on your car.



This is a common scam used to stop people from worrying about why a car has a suspiciously low price.

Helluva scam if the guy put on his uniform twice to show me the car.

I bought the car well under $5k and I'm sure there's plenty that needs to go into it but I've got service records back to the 90s. A replacement dash/door panels, a brand new timing belt/02 sensor/cat back exhaust and the car runs good just not quite perfect.

Does anyone have any experience with those silicone vacuum hoses they sell on ebay? There's generally two kits, one for $35 and one for $125 with about 3x the length plus a hose cutter and instructions. Figured if I'm in there searching for possible vacuum leaks then might as well replace the hoses.

[AaronM]

Originally Posted by HWG09

Helluva scam if the guy put on his uniform twice to show me the car.

Not saying it can't actually happen sometimes, but I've seen a lot of folks unknowingly buy junkers because they thought the reason for the low price was someone going overseas when the real reason was that the car was a money pit waiting to happen.

Originally Posted by HWG09

I bought the car well under $5k and I'm sure there's plenty that needs to go into it but I've got service records back to the 90s. A replacement dash/door panels, a brand new timing belt/02 sensor/cat back exhaust and the car runs good just not quite perfect.

With an oil pressure gauge that drops to one bar at idle, there are potentially bigger issues than something being "not quite perfect."

And with that new timing belt, did he also change the rollers and water pump? If not, how old is the water pump? It should be changed every other timing belt.

Still, I'm pulling for you and hoping you got a good one. Looking forward to photos once you have it.

[HWG09]

Originally Posted by AaronM

Not saying it can't actually happen sometimes, but I've seen a lot of folks unknowingly buy junkers because they thought the reason for the low price was someone going overseas when the real reason was that the car was a money pit waiting to happen.



With an oil pressure gauge that drops to one bar at idle, there are potentially bigger issues than something being "not quite perfect."

And with that new timing belt, did he also change the rollers and water pump? If not, how old is the water pump? It should be changed every other timing belt.

Still, I'm pulling for you and hoping you got a good one. Looking forward to photos once you have it.

I haven't driven it enough to determine if that oil pressure gauge is accurate. Will do so hopefully this weekend.

Water pump was changed last year if I'm not mistaken but I have a receipt for it.

Before I start cutting off vacuum hoses I'm going to swap the fuel filter and check the records to see when the last tuneup was. Maybe pull the plugs to see how they're looking.